The answer is: Because he was a man of war

1 Chr 22:8

King David, renowned for his valor and captivating heart for God, faced a unique predicament regarding the temple’s construction. Though he envisioned crafting a magnificent house of worship for God, his past as a warrior came to overshadow this ambition. "You shed much blood and fought great wars," God conveyed via David's son Solomon (1 Chronicles 22:8). It’s fascinating to note that even though David earned acclaim for his military victories, this very association with warfare disqualified him from this sacred task.

This incident serves as a poignant reminder of God’s preferences for peace over conflict in places of sanctity. Interestingly, the promised-building was entrusted to Solomon, who, reflected in his name, means "peaceful." As a ruler without blood-soaked conflicts to define his reign, Solomon embodied the peace required to build God's temple.

David’s desire echoes an important theme throughout the Scriptures—the transition from chaos to peace, from war to worship. It paves the way for a significance found in building spaces dedicated to quiet reflection instead of expressions of conflict. Additionally, this narrative relates to the overarching biblical concept of a Holy Land where divine peace is established, making it not simply a geographic location, but a deeply spiritual objective.

Ultimately, though David's hands were not involved in the construction, his heart echoed within every stone—seeking to honor the Divine in temple and spirit alike.